Lipid Flip-Flop Driven Mechanical and Morphological Changes in Model Membranes

TL;DR

This study uses simulations to explore how active lipid flip-flop affects membrane shape and tension, revealing steady states and transient morphological changes like budding.

Contribution

It introduces a simulation-based analysis of lipid flip-flop effects on membrane mechanics, highlighting differences between symmetric and asymmetric flip-flop impacts.

Findings

Symmetric flip-flop raises membrane temperature and lowers surface tension.

Asymmetric flip-flop causes transient membrane budding or blistering.

Flip rate influences the extent of morphological changes.

Abstract

We study, using dissipative particle dynamics simulations, the effect of active lipid flip-flop on model fluid bilayer membranes. We consider both cases of symmetric as well as asymmetric flip-flops. Symmetric flip-flop leads to a steady state of the membrane with an effective temperature higher than that of the equilibrium membrane and an effective surface tension lower than that of the equilibrium membrane. Asymmetric flip-flop leads to transient conformational changes of the membrane in the form of bud or blister formation, depending on the flip rate.